Wrong writing posture is one of the major causes of myopia and scoliosis of school-aged children, and wrong writing posture often results from wrong pen or pencil gripping posture.
Generally, common wrong pen or pencil gripping posture includes the thumb overlapping the index finger and the index finger overlapping the thumb, respectively illustrated in FIGS. 1A and 1B. Adopting such a wrong pen or pencil gripping posture to write will, in a long term, result in health problems such as myopia, strabismus, twisted hand and scoliosis.
Various commercially available pen or pencil grippers have been proposed in order to correct the writing posture of a user. However, these grippers are not satisfactory due to the following drawbacks: their complicated shapes lead to production difficulty and high costs; the strange shapes fail to excite the interest of users, particularly school-aged children; the concave finger positioning design is only suitable for static pencil or pen gripping but not suitable for dynamic writing; they are only applicable to writing instruments of a certain diameter or specification; and the process of assembling these grippers with pens or pencils and disassembling them tend to be troublesome.